Should decode punycode:

. http://xn--n3h.net/ .

. http://☃.net/ .

Invalid punycode:

. http://xn--xn.com/ .

Invalid punycode (non-ascii):

. http://xn--γ.com/ .

Two slashes should start a domain:

. .

Should auto-add protocol to autolinks:

. test google.com foo .

Should support IDN in autolinks:

. test http://xn--n3h.net/ foo .

. test http://☃.net/ foo .

. test //xn--n3h.net/ foo .

. test xn--n3h.net foo .

. test xn--n3h@xn--n3h.net foo .